Cryptology ePrint Archive: BibTeX Citation of Report 2009/617

@misc{cryptoeprint:2009:617,
    author = {B. Umaprasada Rao and  P. Vasudeva Reddy and T. Gowri},
    title = {An efficient ID- based directed signature scheme from bilinear pairings},
    howpublished = {Cryptology ePrint Archive, Report 2009/617},
    year = {2009},
    note = {\url{http://eprint.iacr.org/}},
}

You will need the url.sty package (comes with most LaTeX installations) for the last line. Otherwise, remove the \url command.